Not sure if the 90-92 had a MAF I dont recall. It might.
HO firing order is different from a standard 5.0.Maybe I am preaching to the choir here, sorry.
Grab the fuel sending unit so you can mod the one you have with the newer OE stuff. At least you can "bone It" for the pump hanger and such to fab a new setup for the getup.
I think the Airflow density systems ( MAF) perform better than the speed density setups ( MAP), and the mileage is better too, believe it or not.
Also fuel fittings lines and anything fuel related should be scarffed.
Nylon line is easy to work with and works well. It can be bought in 25 or 50 foot rolls too, so you can make a seamless run from front to rear.
Fact is stranger than Fiction