So I have a 1990 240 5 speed and someone tried to steal it a while back and I haven't been able to use the key to lock the doors ever since then but I bought a couple 1-2 channel receivers with key fobs I just haven't been able to successfully install them for keyless entry... Any tips or video links out there that might help?

 

If you install a system that uses remotes to unlock your 240 -
Today - when you turn the key, a switch that is actually wrapped around the drivers key tumbler sends signals to lock or unlock 3 doors and the trunk. The drivers door lock is mechanically pulled or pushed. The remote system will do the same thing - The drivers door will not unlock or lock with your new remote system until you find and install a used door lock motor and associated brackets and connecting rods - and run wiring to the newly installed drivers door lock motor from the door lock relays located near the center dash vents. (I installed a system in my daughters 240. Easy for me, had access to parts and fixed Volvos for a living)

It might still be possible to order a new keylock for the drivers door from Volvo. You can/could order them from the VIN number and the tumbler would be manufactured to work with your existing key. Other choice is a used tumbler - but then you would need to carry 2 large keys. Some Volvo tumblers come apart easily and can be "rekeyed" (glove box lock is an example) But unfortunately the door tumblers do not come apart easily to be able to rekey them.

If the central locking switch in the drivers door is broken - I think they are no longer available.