I'm aiming to upgrade my cooling for towing.
I ordered a 'Heavy Duty' (as opposed to 'Standard') radiator from Rock Auto, and received a CSF 3174 unit which is 1.25 inches deep.

However, my VIN 'spec-check' told me I already have 'Heavy Duty Engine Cooling'.

I'm not sure what depth my existing R/T Magnum radiator has.

One kind fellow on this forum told me that there were 4 types of radiator for the Magnum:
1. Heavy Duty (0.5" deep)
2. Severe Duty (0.75" deep)
3. (1.75" deep)
4. Maximum Duty (1.75" deep with extra crossovers)

This makes me think that 'Heavy Duty' is in effect the lowest size available, so maybe my new 'Heavy Duty' unit is larger.
But my new unit's 1.25" depth doesn't match up with these sizes given here.

Is my new unit actually a 'Severe Duty' unit..?

Rock Auto list a 'Service Duty' unit (which I suspect is a typing error and should actually be 'Severe Duty') and also a ' ' unit for the Chrysler 300, not the Magnum (which is why I didn't buy one of these units in the first place), but doesn't give any dimensions to correlate where these units might fall in this scheme.

If anyone can shed any light on:
1. which units have what depth
2. which unit my R/T currently has
3. which unit I've been sent by Rock Auto
4. if a unit for a 2005 Chrysler 300 will fit my 2005 Magnum R/T without any modification
5. and where I may get a 'Severe Duty' unit from for a reasonable price,
I'd be most obliged.

Thank you! Regards - D