Recommendations

Looking for a little advice here my wife due to medical condition does not enjoy penetrative sex where she is willing to pegg me which I thoroughly enjoy It does very little for her physically so i was looking for a vibrating toy that fits inside the harness but does not go inside her everything I've seen looks big balky or goes inside any recommendations would be appreciated for a toy that hits all the right spots p.s. she does love clitoris simulation

Depends a bit in which harness you have and how much you would like to spend but have a look at this category https://www.lovehoney.co.uk/sex-toys/vibrators/butterfly-vibrators-vibrating-knickers/ . The knicker style ones may lay on the straps on the harness or she could wear knickers with them. Some harnesses do have a pocket for a bullet in the front

Alternatively one of the smaller Womanizers such as the starlet or the Liberty or even the We-Vibe Melt May sit on the harness straps/in her underwear and the suction might help it not move too much