I have just put a new crate engine in my 76 Corvette and obviously the distributor had to be moved from one engine to the other, every manual I read says mark the distributor and on re assembly line up he marks, not very helpful when I obviously do not have marks.

To get the distributer timed close enough to start, you'll need to pull the #1 spark plug. With your finger over the spark plug hole, turn the engine over(or have someone "bump" the key) until you feel compression. Stop, and look at the timing mark on the balancer. It should be close enough to see. Then turn the engine by hand the same direction as it would normally turn until the timing mark is lined up with the "0" mark on the timing tab.
This will have the engine on the compression stroke of the #1 cylinder.
If you look down into the distributer hole in the engine, you'll see the oil pump driveshaft. It has a slot in it. On the gear end of the distributer, you'll see a flat drive "lug" inside of the gear. You will need to turn the distributer shaft to line up somewhat with the slot in the pumpshaft. I say somewhat, because the dist. shaft is going to turn a little as you drop it into the engine. It may take you a time or two of trying, but it will go down.
Put the dist. rotor on the shaft, and then start installing the plug wires from the terminal that the rotor points to. That will be #1.
(If your plug wires are already installed into the cap, all you need to do is turn the rotor to point to the #1 wire terminal when you drop the dist. into the engine.)
Hope this is somewhat understandable.

Yes, you can eliminate the EGR set-up, and use the block-off plate. The EGR has nothing to do with dist. vacuum. Dist advance vacuum should come for directly off of the intake manifold, OR...from a ported source on the carb, depending on what type of distributer/ignition system you have.

OK lets see how well I can explain this. If you have the HEI dist the the #1 position on the cap is on the left side. It is the second post clockwise from where the 12V power connection is on the cap.  I set the initial timing by bringing #1 up on compression and then rotated the crank until the damper marked aligned with 0 or TDC on the indicator attached to the timing chain cover. Then I dropped the dist in and tried to clock the rotor to about where the #1 post will be sitting. I placed a mark on the side of the distributor that was in line with the rotor and installed the cap. I looked at where the mark was in relation to the #1 post and made a minor adjustment to the distributor so #1 post fell in line with the rotor position. When I checked the timing with my light it came out just a little retarded. NOT ME . Was close enough to start. If you get a pop back through the carb stop and check that none of the plug wires are on the wrong plug. If that looks good than the timing may be a bit retarded so stop and check the rotor position. It worked for me but I am sure there will be other methods that memebers use. Good luck suncountry2008-02-05 20:08:49

OK, sounds simple enough, I assume the slot on the oil pump and the 'dog' on the rotor shaft is offset, so I cannot put it in 180 degree's off ?

Boy am I glad i asked, these tips will be very helpful, you guys are great, I am sure the new owner(who ever that is) will appreciate me doing all this (yes I have to sell my baby when I have put it all back together)I am buying a house and three classic cars is a bit excessive, and I am limited as to which one I can sell, I will be very sad to see her go

i just re-read my post and think i have aswered one of my questions and that is that the 'dog' on the distributor is not offset as it is only ther to give drive to the oil pump and has nothing to do with the timing.

[QUOTE=JagVette]i just re-read my post and think i have aswered one of my questions and that is that the 'dog' on the distributor is not offset as it is only ther to give drive to the oil pump and has nothing to do with the timing. [/QUOTE]

Yep, the dist will go either way, but the wrong way, it will be 180 degrees off. If ya wanna cheat when that happens, just move the plug wires around, instead of pulling the dist back out.
(I'm so lazy, ain't I?)