Yeah you've got to knock the nubs down for the link bar "v" clearance, and a little bit in the Valley above the lifter bores. The Morels are very strong and work really well but the lifter body itself is a good bit taller (the cup is higher) than many other Solid Roller designs. So the amount of grinding needed is a bit more than with others that comparatively just about "drop in". The Upside though is this also means your pushrods wind up being substantially shorter than with other brands. Also it will alter the "touch" clearance areas needed in the heads for the pushrod arc. I actually like the shorter pushrod because it's comparatively stiffer and lighter, I used 11/32 Mantons on my 414. Another advantage of the Morel
is the body is so long there's virtually no chance of the lifter coming out of the bore due to a rocker/pushrod failure so the chance of catastrophically losing Oil Pressure through the galley is pretty remote.
As for oiling mods, my Cam has grooved #2 and #4 journals and on this one I didn't open up the mains passages. I mainly concentrated on opening up the #5 main cap to 1/2" and porting and polishing the pump, I'm running a rear sump Truck pan. The cam is a Dodge 358" IROC Cam Motion Grind from the mid 90's and I'm not planning to spin it up much more than 6800 so I didn't see a need to do the full high RPM barrage of oiling tricks.
Here's a pic: