Can anyone explain how to do this or have pictures of this? I’m putting in a solid roller and was told that I should banana groove my shafts to deal with the added spring pressures.

I believe with a small triangular file. I have not done it yet but I plan to I just need to find an orig banana grooved shaft so I can duplicate the angle/depth but I dont it has to be exact just so it will spread the oil out more on the load bearing surface

I learned about it in a Mopar Muscle article:

360 Budget Rebuild: Double Take 360 Pt. 1 December 1999
360 Budget Rebuild: Double Take 360 Pt. 2
January 2000
360 Budget Rebuild: Double Take 360 Pt. 3 February 2000

Just cut a grove in the rocker shaft at a 45 degree angle centered on the oil hole. I don't remember if it gave specifics on depths or lengths.

Dremel tool works great..

Hughes engines sells them. Maybe you could find a picture of one on their website. Dave

If you have access to a Bridgeport, Use a ball end mill.

Cutoff wheel

So, it looks like a small cut off wheel at an angle will do it right? Does anyone know why the groves are at an angle as apposed to parallel with the shaft?

So that the oil will have a tendency to drain of onto the shaft rather than lay in the groove. Also the angle will make the groove slightly longer under the rocker than a straight across groove. Make sure to smooth any burrs that the wheel leaves on the edges of the groove while cutting.