I think this will PREVENT burn-outs - Voltage Regulator/Rectifier Improved Mounting - UL350iS

[@littlewingpsc27]

Still looks like a fairly good size gap between the voltage regulator and the mounting plate. Did you consider adding a metal shim to fill more of that in, in addition to the paste?

[@earlbenge8904]

You've done a really smart thing there with the with a dialectic paste and if it still gets too hot you need to take and put a heat sink on your the plate that you installed on the other side

[@joevillan892]

Quick Question... How do you know which plug on your regulator is the ground and positive? Did the regulator come with a diagram or does it have the + and - on it?

[@Tokter]

That looks like way too much thermal paste. To achieve the best heat transfer, the metal surfaces have to touch. The paste is just there to fill the microscopic imperfections between them, that wouldn't touch each other without paste. With so much paste, the heat transfer is worse than without paste.