Originally Posted by r3dn3ck

You've got the skills... you could build up and weld a setup like Richard Holdener's custom intake that they tested on the 4v 4.6 and 5.4's. All you'll need is a plate that can mount to the head and then you can start adding plumbing to air and water. Use adjustable hose like bits of radiator upper to allow you to adjust the runner length and couple those in to a big box with a TB mount on it.

The returnless systems have exactly the same problem as the supra on the last injector. It ends up being the whole driver side bank on returnless mustangs but it's the same problem of pressure drop causing lean out.