plumbing help for VarioS-4 return pump on Reefer 170

[SFREEF3R]

I could use some help finding simplest way to attach this return.

The Reefer 170 return line is a 5/8" ID tube (*I think*)

The VarioS 4 has a few different options a 1" slip PVC fitting and an 1" barb fitting (which can be reduced to 3/4" barb)

Trying to find the simplest/cleanest way to do this. Any help would be appreciated from those of you with more plumbing experience.

 

[ShepherdReefer]

Are you trying to decide if you want to hard-pipe or soft-pipe the VarioS4?

 

[SFREEF3R]

I’m want to use the 5/8” tube but trying to find the most efficient way to connect. At this point I’m thinking of using the 1” Slip union supplied with the Varios and connecting it to a 1” spigot x 3/4” FPT fitting. I can then get a 5/8” barb X 3/4” MPT fitting to connect to that.

 

[SFREEF3R]

3/4" NPT x 5/8" Barbed Straight Reducing Fitting - Indelco
1" Spigot x 3/4 FPT

attaching to the in box union - looks something like this (but I think the threads on the pump are metric):
https://www.bulkreefsupply.com/schedule-80-union-slip-x-thread.html