I'll answer your thruster question first. Open st_equip.ini in the Equipment folder, and you'll see something like this

[Thruster
nickname = ge_s_thruster_01
ids_name = 263737
ids_info = 264737
DA_archetype = equipment\models\st\ku_thruster.3db
material_library = equipment\models\ku_equip.mat
HP_child = HpConnect
hit_pts = 1000
explosion_resistance = 0.500000
debris_type = debris_normal
parent_impulse = 20
child_impulse = 80
volume = 0.000000
mass = 10
max_force = 72000
particles = gf_ge_s_thruster_01
hp_particles = hpthrust
power_usage = 165
lootable = true
separation_explosion = sever_debris
LODranges = 0, 20

Change the highlighted line to power_usage = 0 and presto, unlimited thruster

If you want your Rhino to have more weapon power, open misc_equip.ini in the same folder and scroll to this:

[Power
nickname = li_freighter_power01
ids_name = 263722
ids_info = 264722
volume = 0.000000
mass = 10
DA_archetype = equipment\models\hardware\li_fusion_reactor.3db
material_library = equipment\models\hardware.mat
capacity = 1300
charge_rate = 126
thrust_capacity = 1000
thrust_charge_rate = 100
lootable = false

Those four lines affect the power. They're pretty self explanatory. One thing, though, if you want only the Rhino to have unlimited thruster power, don't change the thruster entry in st_equip, change the line "thrust_charge_rate" and "thrust_capacity" to something like 10000

Thanks! Now what are the entries in the goods.ini file for the Rhino, so I can increase the power of its shields. Or, how can I increase the power of its shields by changing the stats for the actual shields? I think I can do that by myself, but what is the Rhino entry in the Goods.ini file?

Hi Chris03
The entry for the rhino in the goods.ini is "lfr_package". Under this there are some lines and also this line "addon = shield01_mark01_fr, HpShield01, 1". This is the shield mounted on your rhino, if you buy it. Change it to "addon = shield01_mark03_fr, HpShield01, 1" to get the best shield to mount on the rhino.
If this is not enough open up the shiparch.ini (in Freelancer/Data/Ships). Search for "li_freighter". In this block you will see these lines:

hp_type = hp_freighter_shield_special_3, HpShield01
hp_type = hp_freighter_shield_special_2, HpShield01
hp_type = hp_freighter_shield_special_1, HpShield01

It means that the rhino is able to mount class 1, class 2 or class 3 shields. Add these lines to make the rhino able to mount up to class 10 shields:

hp_type = hp_freighter_shield_special_10, HpShield01
hp_type = hp_freighter_shield_special_9, HpShield01
hp_type = hp_freighter_shield_special_8, HpShield01
hp_type = hp_freighter_shield_special_7, HpShield01
hp_type = hp_freighter_shield_special_6, HpShield01
hp_type = hp_freighter_shield_special_5, HpShield01
hp_type = hp_freighter_shield_special_4, HpShield01

If you want to change the power of the shields, look in the st_equip.ini (FL/Data/Equipment). Every shield has the lines

regeneration_rate = xxx
max_capacity = xxx

Change this to higher values to make the shields stronger.