Need to Find a few things out before I get started....

[Mustang5.0HO]

Ok well I got some money for christmas...now I got 400 but Im only gonna be able to spend 200 or around there(g/f preseant is DysneyLand)...anywho...I got a friend that works with Trucks and he has a shop that does rear ends....he's 17 and I think he knows whats he's doing...he said he would put my gears in for 100 bucks...that sounds good...but Im wondering if he will put the right gear oil and such...he said he can do it on sat put gears in...He said I dont need the gear install kit...now...Should I go for it for 100 bucks or buy the install kit and all that...I will be broke after that..2nd. Im FINALLY buying an O/R pipe...now Im planing on going MAC since it comes out cheaper than BBk...but thats where im worried...I know BBk > MAC but Im money tight here...where can I find a cheap O/R H pipe for my 91 5.0?? If anyone can help me out with links and such...and one more thing...when I put my gears in what else should I do?? because I heard my speedo will be off by 5 mph or something.. thats all...thankz

[Mustang5.0HO]

Found this deal out so far
http://www.latemodelrestoration.com/...em_no=MAC-8693 1&comp=LRS

[YsOffcr]

I have a full Mac exhaust(headers, prochamber, and cat back) and have had no problems with it.