Welding Tips and Tricks

What would be the best mig wire or tig filler rod for welding 5160, 1070 or 1080 to A36 or 1018 steel?

I have been finding a lot about preheat and post heat but not finding any specifics on filler material.

I have a Hobart Ironman 230 with Lincoln Super Arc L-56 in it right now.

Thank You

I like ER312, not saying it's the best out there, but it's used often for welding dissimilar and high carbon steels. I've had excellent luck using it to weld AR400, whatever grader blades are made out of etc.

309, 310, 312. Watch the pre heat and post heat.

best? no idea.
me, i would use 312. its a good "weld anything" rod and especially harden steels.
2nd would be 309.