I don't believe a TRUCK 302/5.0 were true hydraulic roller engines until around either late 1993, or mid year 1994. Someone correct me if that's wrong.
I know the Mustangs were hydraulic roller engines from mid 85 to 1995.
My prior 87 Bronco's original engine was a flat tappet cam, speed density engine. The replacement engine intalled into it was a 1996 Bronco hydraulic roller engine and I also kept it speed density as well.
My current 1994 Bronco's original 5.0/mass air equipped engine blew shrapnel all over the highway at 169k - and I just replaced it with a 2000 Explorer 5.0 GT40P shortblock, using the GT40P heads as well. No issues as far as bolting up the Bronco intakes to it and the Bronco front end accessories, etc. Granted, some things are different between the original 1994 Bronco 5.0 and the 2000 Explorer 5.0, but you need to know about Ford engines and how to go about making it work for your specific application.
Cobra Jet is correct, an 89 Truck 302 is not a roller cam engine, although, you could make it one, you need to drill and tap the block so that you can bolt on the spider spring that holds the little "thingys" in place that keep your lifter from turning.
On the manifold, are you talking about the truck intake, or a mustang intake??
Tmoss will only port a mustang lower intake if I remember right.
I thought all 302's after 85 were "roller ready" in that they were tapped and could accept the roller cam. The trucks did not get the roller cam like said above until much later, and the 351 did not go "roller ready" until 94 or late 93,
You should not even have to tap the spyder hold down bolts.
The stock mustang upper flows around 190cfm you realy dont need to spend the time porting it and yes Tmoss ports the lowers 99.999% of the time, but does port other intakes.
He ported my explorer lower, and I know he has ported some edlb. lowers.