OK to replace P-series with L-series tires on '89 montero?

[ranran]

Hi everyone!

I have a question relating to the use of P-rated or LT-rated tires.
I have a 1989 Mitsubishi Montero (old, but we love it!). The OE tires
were Yokohama p235/75R15 105S and are quite worn.
I like the Yokohama tires, and after researching, wish to replace with the Yokohama Geolander HT/S series (G051). However, I can't decide between the "P" or "LT" version.

STATS:
Geolander HT/S P235/75R15 108S
Geolander HT/S LT235/75R15 104Q

We live in a snow belt region and do go offroad a few times a month (
nothing really major, mainly unmaintained dirt roads, some steep hills and such). We also *never* go faster than ~70-75mph MAX so I'm not too concerned with the lower speed rating of the LT.

I was therefore thinking of changing from the Passenger version to the
Light Truck (LT) version. Is there any "danger" or problems in doing
this?

I've tried looking online, but besides one comment about not switching (
and *no* info as to why), I can't find the answer!

cheers!

Randall