8D is a starting battery, so they have massive current output but weak on sustained power. The L16s will be fine.
To give you an idea, I have 6 golf cart batteries that are very old now. they are 6v at 230AH, Series parallel configuration gives me 12v at 690 AH
that's 8,280Wh with 4,140 available, this runs my house, Computer at 150w for up to 6h a day, fridge, lights, and at their current age will run things through the night on an 1800w nominal 2.5Kw peak inverter.
Solar array is 540w, that is undersized, I really need 3Kw to have excess power, but the battery bank is good enough (I'll add one more set for a total of 920Ah)
Because again all it needs to do is run the house over night which is fridge, and phantom loads. For prolonged bad weather I have a genset, and I am making a wind turbine to supplement them.
Summer my 540w panels make an average of 5 to 3 KwH, Winter 1 to 2.5KwH of total energy, this needs to run the house and charge the batteries (Which brings us back to not enough panel and why my batteries are in such bad shape)