I will take a stab at it.

Unballasted 4430 QR w/ SGC is 11,350 (3380/7970)
148 loader weighs 1350 and places 90% of weight on front axle
A 4430 should not need much more than 4 weights per side for a loader so you are talking 13,900# (balllased to 110#/hp with a 4600/9300 or 33%/67% weight split)

According to Bushhog
4815 weighs 6200# with 2200#tw and 15'3"long
3815 weighs 6000# with 2200#tw and 15'3" long
2815 weighs 5500# with 1900#tw and 15'3" long
1815 weighs 4600# with 1700#tw and 15'2"long

With a 4430 on front I doubt it would be the 4815 but more likely an 1815 or 2815

Since a 4430 is 161" long, add a few inches for loader mount and you are at 165".  Put drawbar in short position and overall length from front of loader mount to rear of mower is aound 28'.
A 34'gn will have 29ft of flat deck so you can pull on, flip ramps, and backup to reduce tongue weight.

Now with a 2815 in tow and short drawbar the 1900#tw will transfer approx 500# off front axle to rear making the axle weights 4100/11700/3600 and total 19,400.  Put this on a 34'gn trailer and you can backup about 9ft.  Solving the static diagram you will find that axle 1 @ 4100# and 16 forward of tandem, axle 2 @ 11700 and 7ft forward of tandem, and axle 3 @ 3600 and 9ft behind tandem, since hitch to tandem center is 34 that means 3380 is added to tw and 16,020 is added to trailer axles.  Assuming 8400# trailer with 1400#tw empty that is 4780tw and 23020 trailer for 17%tw.  Our CCLB SRW 3500 Dmax has a GVWR of 12,800# and weighs 8020 empty bed, add 4780tw and truck is at its 12,800GVWR while the combination is at  35,820 with our 8400# 34' PJ trailer which is over the 30,0000GCWR.  Put a 3500 dually in front and it is legal all day long.

My biggest concern would be bottoming out the mower on the ramp.

ETA:
No wheel weights and the 1815 mower should be even easier and so would a 36' trailer.  Remember, there is nothing prohibiting setting the loader on the GN.