In more than 90% of cases, ML and run line is one plus and the other one minus. This is what I do with a calculator (In case you don't have spread sheet handy). Let's say the numbers are -X, +Y. Betting on -1 or +1 line is always risking X+100 to win Y+100. And you can use calculator to do a division to get the line.
For example
+1.5 -162, ML +128 => risk (162+100) to win (128+100) => -115 for +1
-1.5 +152, ML -136 => risk (136+100) to win (152+100) => +107 for -1
Hope it makes sense.