I have a few question about the top half of a slant.

First do late hydraulic heads interchange with solid lifter heads by changing valvetrain

Second I would like to stop the constant valve cover leak has anyone tried the clifford alluminum valve cover and have they fixed their problem with filling orders in a timely manner. Is it available in the later valve cover bolt pattern?

Third do the hydraulic lifter head's supply more oil to the rocker. My valiant's head is sinking it's valves and I have a pair of spare hyd. heads but no good solid lifter heads. When I had the valve cover off yesterday for another valve adjust it was oiling very poorly. thanks in advance

F.Y.I., I had a chronic valve cover leak as well, but I figured out that the previous owner had over-tightened the hold-down bolts and bent the edges around the bolt holes. I turned the valve cover upside down and used the handle-end of a screwdriver as a "punch", tapping the area around the bolt holes down a bit. Reinstalled with a new gasket, and it hasn't leaked since.

Although if you want a cool-looking new valve cover, there's nothing wrong with that, either!

VM

You can swap over to the hydraulic head and "mix & match" parts by using the adjustable rocker arms and push rods, you will have to use the smaller rear hold down bolt from the hyd. rocker shaft and the valve cover.

Or look around for the earlier SL6 head, they are around.
ebay SL6 Head
DD