3.5 into p38 (ex- 4.6)- would it work?

Hahaha, isn't homophobia fun!!

yeah, but non v8 landies are still gay, unless they are v12

I'll just laugh as I chug past you broken down by the roadside in my diesel (I wouldn't really I'd do the honourable landy thing and stop to help) nice looking rangie!

all landies break regardless of fuel

You know what and this may be a bold statement but I reckon more diesels have serious trouble than v8s. Well, 3.5 anyways, the only one you can trust.

Diesels are always turbo or headgasket or timing belt or rocker arms or whatever, ok ok v8s more often have the bonnet up but that's the ignition system, the v8 ends up shagged after 75k but it keeps running nicely for a very very long time, I mean there isn't much that tends to stop a 3.5 in a serious way apart from HGF which is pretty rare.

and a 4.5

Well yeah but thats such a rare item I discounted it, but the same applies.