I am trying to find some information on how to wire or bypass the starter relay to the clutch safety switch and the neural safety switch on my 1971 Dodge Challenger manual transmission. I don't have the clutch safety switch and they are hard to find.
Any info or pictures would be appriciated.

Run a short jumper (1/4 female terminal/ring terminal) from the male "grn" terminal on the starter relay to ground (under SR mounting bolt works fine). this will allow it to crank in any gear position when you turn the key to start

It may cause more damage then a switch. Just 1 time you forget
Bob

Do I have to worry about electrical shorts or fires running a jumper?

All the clutch switch does is ground the starter relay. There is a starter relay made to be self grounding for the manual trans cars that didn't come with the clutch switch.

Classic Industries makes a wiring harnass that incorporates the neutral safety switch and the backup lights. Can I use this harnass if I jumper to ground on the starter relay?

Yes

I would probably wire in a small toggle switch and put it on the bottom edge of the dash, below the light switch panel. It would be a momentary spring loaded switch that would not let you start (turn over) the engine until you actually hold the switch and close the contacts. As soon as it starts, and you let the switch spring back it will not engage if the key is turned until the switch is again pushed to allow it to start. This is a manual means taking place of the clutch safety switch. Yes those originals are hard to locate, bet brewers would have them though.

The starter relay for the manual transmission cars have only one terminal on the bottem of the relay. Why only one whem automatic cars have two?