Help needed finding sources to modify model cars

I have a number of recent release 1:18 models that I would like to switch out parts from one model to another.  Example:  Two models and just switch out interiors from one to another.  Example:  Take the hardtop from one model, making it a convertible and adding the hardtop to a convertible model making that model a hardtop.

I am too old, no expertise, or tools to make these modifications myself.  Trying to make two scale models of cars I had in the past.  Really feeling old today as I spent hours going back in favorites lists from three computers ago.  Any sources I saved from two decades ago web links no longer work, or people out of business, or died.

Finally, after decades of waiting, two of my favorite car models have been recently released in 1:18 scale, and with only switching out parts I can get replicas of cars I have owned.

If anyone has a contact that can help me with switching out parts on some 1:18 scale resin models I would be thankful.  Just can't do it myself.  Of course willing to pay.