Depends on which LA heads you use as to whether you use the Performer intake as is. If you decide to use aftermarket heads like Speedmaster, etc, you can use the Performer and just port match the intake ports to match the larger ports on the heads. Same holds true if you were to use 360 heads. If your existing 318 heads are not cracked and can be reworked with a valve job and surfacing, just bolt the Performer right back on as is. You will be miles ahead if you use the hydraulic roller lifters and cam from a 5.2. You could sell your flat tappet cam kit, or return it if they aren't going to charge you out the ying yang for a restocking fee. If you find a decent 5.2, you could send the cam that is in it to Oregon Cam Grinders and have it reground to a slightly more performance oriented version. You could clean and check the existing hydraulic roller lifters and reuse them as well. There are people on here that have done that very thing and can coach you thru it. I'm not so old that I've forgotten being 24 and on a tight budget.....so I get it, lol.