Leave it up to you Dave

If you want to do this swap yourself.
A. Virtually any trans will work but a 200r4 or a 700r4 is your best bet for a overdrive trans.
If you want to have a lockup trans you will need a lock up converter. Also might think about a 4th gear lockup only kit. You will have to drop the pan to hook it up. It is an easy job. Also TCI has a constant pressure valve body kit which supplies 200lbs of pressure to the trans so you dont fry it before you get the TV able set right. (stacking the shifts at a lower pressure which will destroy your clutches in a matter of a few miles)
B. You will have to cut the exhaust pipes to remove them from the crossmember. Try to make a clean cut so you can weld them back together easily. This would be a good time to replace the pipes with any type you want unless they are in good shape or dont want a different style.Also the universals and trans mount. You will have to cut down the driveshaft anyhow. The crossmember from Bowtie will let you install any size/type pipes you want because the pipes fit under the CM rather through it as the stock CM does. I straightened out the section of pipe there to the headers . Nicer fit. When you put the pipes back on do yourself a favor and rap the pipes and as much of the header with exhaust heat rap.(Makes for quieter, cooler corkpit). I did mine back to and on the mufflers which are modified chamber pipes. It works also to quiet the ringing these pipes are notorious for.Be sure to spray a silicon high temp paint on the rap to seal and keep it from absorbing oils. I used .060 safety wire on the ends of the rap to hold it. The wire clamps that they sell with the rap are crap.Turn the ends of the twisted wire back onto itself (make a loop)so you or the next guy dont get poked. Dont use .030 wire it breaks to easily
When you hook up the trans be sure the torque conveter is fully seated on the shaft. There should be a backspace (into the trans) from the bell housing flange of aprox 1/2-3/4" (check to make sure exact dimemsion) otherwise you can have bad things happen to the T C. There is a little ring type clamp on the front of the trans that is used to keep the seal in. It was GM's fix for trans fluid getting behind the seal and popping it out.
Bolt the TC loosly at first (just before they bottom out) to the flexplate so you can align all the bolts. Otherwise the last (third) bolt will be a biotch orl not fit. Then torque them to spec.
When you bolt the trans to the engine line up the guide pins and put the lower 4 bolts in. This is where a trans jack adapter comes into play. Lower the jack and let the trans pull the motor down a little so you have access to the top bolts. Also it is easier to hook up the trans cooler lines. Before you do this part be sure to remove the distributor cap from the dis and any other hard lines attached to the motor. Otherwise you WILL break the cap or lines. Not that I ever did that. Hmm.There are a few more tips I can give you but this post is getting a little long. Kevin, if you need any one on one let me know. I will give you my tele # if you would like.custom762008-02-15 18:47:32

This topic was covered several months ago and there is a thread with more good info. Try;

Nov. '07 700 R4 lockup thread

DaveAutom8r2008-02-16 07:27:25