the Small 6 is not much longer than a SBF, shouldn't need to do anything to the firewall, prolly have to run an electric fan tho. the small 6 can be built up to over 300 HP, using forced induction and still have good street manors. they can be built to 300 HP N/A and still have good street manors. you ither have a 200 or a 250, if a 200, only a small 6 trans will work due to the smaller bolt pattern but a 250 uses a SBF bolt pattern. you can tell by the freeze plug count, more than 4 is a 250, 4 or less is a 144- 200, can't remember the in between counts to tell them apart, only that a 200 is 4 plug. www.fordsixparts.com has plenty of hop up parts. a D.U.I dizzy that is dyno proven 15 HP more on a stock engine, a good selection of cams, headders and a lot more. chrome dress up also.