After a week of deep searching I finally found a solution to fix the problem with old guns and rocket launchers not aiming at the cursor. The problem was in humanoid.TargetPoint, when used with FilteringEnabled it would force all projectiles to aim at coordinates 0,0,0 which is the center of the baseplate. I used that information to search for exactly what I needed to solve the problem, now all the guns are aiming correctly. So how did I do it you might ask? I used a model like this!
https://www.roblox.com/library/167731549/TargetPoint-Fix-for-FilteringEnabled
Basically what the model does is exactly what I’ve been trying to get my old guns to do this whole entire time. Who would have thought that the most secret way to fix old guns was in 2 simple scripts and a remote event? The only challenge was trying to guess how exactly to assemble my own which obviously nobody else seemed to know how to do. Well now that I have a good example I even learned something new myself! I highly recommend that you take this model if you have old tools that don’t aim after the FilteringEnabled update, it will really save you the time and effort I had to go through!