KAC. hardware compatibility between RAS M5 and RIS M4_ tecnical question

Hello i am creating a clone of a colt M16A4.
A guy proposed me a used M5 RAS forend rail at a good price (130 dollars), only it lacks the internal components for the front and rear coupling.
Since I have the upper part of a RIS M4 that I don’t use, I was thinking of transferring the necessary parts to the M5.
Are compatible?
Looking on the Operation parts website they sell the rear kit ( KAC-KNIGHT’S ARMAMENT M4/M5 RAS HARDWARE KIT) and give it compatible for M4 and M5 while for the FRONT HANDGUAD SPACER and KAC-KNIGHT’S ARMAMENT M4 RAS HANDGUAD LEAF SPRING they speak only of M4.

Do you know if it is different?

Thank you

The top front hardware and spring look identical on mine, they install exactly the same way. The cap on the M4 is round, on the A4 it’s a triangle but that doesn’t matter. I recently had them off the A4 but paid no attention re installing.

Thanks for your response