91 GT

So i got a 91 GT for 200 bucks, blown motor but came with a low mile JDM replacement. Car originally had a 5S-FE but the engine that came with it is a Late 90s JDM 3SFE out of a RAV4. It bolted right in and amazingly runs off of the 5sfe ecu and doesn't throw any codes at all. Seems to be a wicked little 3sfe though, really "torquey" lol. Revs really quick as well. Anyhow, i have never owned a 5th gen celica and never owned a celica with a 3sfe in it. Ive owned an 86GT with a god awful 2S-E that was mildly built and still put out less power that a bog standard 3sfe then i owned a 88GTS with a 3S-GE and a 95 GT with a 4A-FE and of course my 88 Alltrac. Anyways Im putting my alltrac in the garage for a while until i can figure out whats causing the weird humming sound when its driving, changed both wheel bearings but still that weird "rotational" humming is going on. So its getting put on the back burned for now and i scored this little 91GT for 200 bones and im going to use it as a daily driver. Its that pale metallic blue with blueish grey interior with a 5speed and power locks and windows. It also came stock with the Toyota Alarm System and a factory CD player, that didnt work very well. So ive dumped the new 3sfe into it and got her running and began to bolt the front clip on, the kid who owned it had it parked under a tree and a big branch broke off and smashed up the hood both front fenders and one of the headlights covers. I found a red 5th gen GT in the junkyard that i got the parts from. I'll post some pics of her once i get her finished and out on the road tomorrow. I had a few questions for any of you 5th gen owners out there. Do you guys know if a 5SFE header will fit on the 96-99 3S-FE. I cant find a 3sfe header anywhere but i figured the 5sfe is essentially a stroked 3sfe and that a 5s header should work. Im looking for a few pieces for the interior as well, like the rear hatch cover or decklid whatever you want to call it.