I was going to order a reproduction tach for my 70 Dart, but Year One has two listed for my application. One is listed with slanted numbers, an the other is with straight numbers. Why are there two different ones and which would be "correct" in a 70 Swinger 340?

69 Super Bee 440 5-speed
70 Dart Swinger 340 4-speed
69 Camaro SS 396 4-speed
66 Cutlass Convertilbe
70 Judge Ram Air III 4-speed
68 F-100 SWB