New voltage regulator and main battery & stalling problems

Recently replaced the voltage regulator and main battery.  I had been having issues getting my starter to engage. I suspected a charging system issue due to the fact my battery failed a load test and I've never addressed my alternator since owning my van.

Since changing out the battery I ran into a starter problem again sporadically.  I've since determined that it is the neutral safety switch (automatic transmission) being the source of the problem.  I've seen a great YouTube video regarding fixing the striker plate by soldering material onto the worn area to save it.  I will be trying that soon as it doesn't seem difficult to do and it saves finding replacement parts if not necessary.

Also recently I was running the van in warm temps (around 30+ degrees Celsius) and having stalling symptoms while travelling at slow speeds such as intersections or gridlock highway traffic.  I changed the distributor cap as it had signs of external arcing (not OEM cap).  Also changed the fuel filter all with the goal of troubleshooting the stalling tendencies...  so far that hasn't solved the problem so will next move onto checking grounds and various sensors to see if I can keep my engine running when that engine bay gets smoking hot.