Mouse too hot ???

Dors anyone have a fool proof method of making sure the thawed food is the right temp.? I think I may be "cooking" my poor guys food in my efforts to get it to body temp. I'm feeding small mice 7 - 10gms. I thaw them in hot water for about 20 - 30 min. then heat it with a hair dryer for a couple more. They end up kinda mushy... my guy has only eaten one of the 4 or five I've offered. He's down to 55gms and looking "very" skinny with a visable spine.
Also, will a heat lamp make it hard for the snake to "see" the prey item? I understand they use heat as a way of finding their food. I have to use heat lamps to keep my temps up. Should I turn them off when I feed?
And one more question.... Is it very important to use a black heat bulb? I broke mine this morning and they only have clear ones or red ones in my town.

be careful u dont cook them....its not pretty. im talking adult rats here but i just leave them defrost a few hours/all day so their soft all the way through. Then i warm them on the radiator with newspaper under neath them only to take the chill off them, not so they are warm through. Then i dip the head in almost boiling water for a few seconds, take it out and leave it cool a couple of seconds so theres no scalding water and offer it like that!

e2a i only leave em on rad for about 20 mins, turning halfway and these are 300g rats!! also they are NOT directly on the rad. with a 10g rat i would give em maybe 30 seconds a side( give the newspaper 10 mins to get up to temp before u put em on there if u do decide to go down this route)