Long story made short: I have a 15" Trinity Force Atlas KeyMod rail that simply refuses to die. It has made it's home for the present time on my precision build, and I've been annoyingly trying to find rail accessories that satisfy my aesthetic preferences. I've seen MLOK accessories forced onto KeyMod rails before, so I figured I would document my attempt just in case some other poor soul is living in 2024 with KeyMod rails still hiding in his gun safe. So here goes nothing.....

Photos are probably pending mod approval since I am new to the forum...

The goal was simple, I wanted a handstop that would stay very flush with the rail and matched my Magpul FDE components. I ordered the Magpul MLOK hand stop kit and set to work.
https://imgdump5.novarata.net/05v49y.jpg

Looking at the spacing of the mounting holes, it seemed pretty straightforward, I opted for the smaller of the two handstops.
https://imgdump5.novarata.net/ws2ark.jpg

Using some flush-cut pliers and a razor blade, I carefully trimmed one of the plastic nubs on the rail-facing-side of the handstop which was enough to allow the entire component to sit flush on the rail while preventing any lateral movement.
https://imgdump5.novarata.net/zgi9dc.jpg

I had to file down the mounting screw to prevent it from touching the barrel. Using KeyMod hardware didn't work in this application because the nubs centered the handstop over the opening of the KeyMod profile rather than the slotted portion.
https://imgdump5.novarata.net/ygu6ks.jpg

The fitment was sturdy enough and I am convinced I could do this with a VFG or other MLOK specific accessories.
https://imgdump5.novarata.net/11yhea.jpg

I even trimmed the nub on the rail covers and they managed to lock into the KeyMod as well. Though the fitment wasn't nearly as stout without any hardware.
Overall, I'm very pleased to have discovered this and hopefully this helps someone else!
https://imgdump5.novarata.net/cjtgz7.jpg

It's definitely secure. I'm certain the polymer would break before the hardware came out of the rail. MLOK t-nuts are larger than KeyMod t-nuts so there is a solid, mechanical connection. Trimming the plastic nub just allowed the MLOK slot profile to nest inside of the KeyMod slot profile.