online is always the cheaper option.

whats the alternator amperage on that truck? and i need a general idea of how much room you have behind the seat for a box.

also you'll want to start figuring out a plan on installing the head unit. they don't make dash kits/wiring harnesses(the wiring is simple anyways) so you'll need to figure out where you want to install it. i did an install is a 78 f250 and we just went with a glovebox install.

This post was edited by Subwoofer on Jun 16 2013 12:22pm

ya i really wasn't about to ruin the stock radio in that 78 lol. i hate doing that to old trucks.

some google results show something like 60 amp alternator. on the low side but it should be doable. you'll also need to upgrade a few wires in your engin*** for this.

how much you looking to spend?

and this is 6.5 inch speakers in the door right?

take a look at these top/bottom depth measurements and tell me which ones would fit behind the seat. need to find a box that fits before i can start looking at a sub for it.

http://www.sonicelectronix.com/item_62709_Ground-Shaker-ST-1-12-BLACK.html

http://www.sonicelectronix.com/item_7548_Sonic-Sub-Box-1T10-0.7-Black.html

http://www.sonicelectronix.com/item_65846_Ground-Shaker-F250-1-12.html

keep in mind there will still need to be room for the sub to mount on the outside of the box. which is like 2 inches to be safe.

http://www.sonicelectronix.com/item_67790_Rockford-Fosgate-R165X3.html
http://www.sonicelectronix.com/item_64092_Pioneer-DEH-X7500S.html
http://www.sonicelectronix.com/item_18212_Pioneer-TS-SW3001S4.html
http://www.sonicelectronix.com/item_65846_Ground-Shaker-F250-1-12.html
http://www.sonicelectronix.com/item_44472_MB-Quart-ONX2.100.html

then the wiring stuff

http://www.knukonceptz.com/productDetail.cfm?prodID=KCA-K4
http://www.knukonceptz.com/productDetail.cfm?prodID=BK-RCA2

then big 3 upgrade with either kca or kandy series 1/0 guage wire
http://www.knukonceptz.com/productMaster.cfm?category=Power Wire

you'll order wire to replace these 3 wires:
alternator to battery +
battery - to body ground
engine to body body ground

you can measure them and get specific lengths or just eyeball them and order a couple extra feet of wire to be safe.(if you want 3 precut you'll need to measure them but keep in mind you order it by the foot and can't get smaller than a foot at a time)

if you need ring terminals they have those as well http://www.knukonceptz.com/productMaster.cfm?category=Installation Accessories

and on this wiring stuff you can probably get away with 4 gauge on the big 3 upgrade to save some money. 1/0 saves you from having to deal with it again though if you get a high output alternator for light trail lights or something.

about the only thing local shops offer over online is the option to hear some of the speakers and play with the head units before hand and of course..the overpriced install work.

support local businesses is always good but the price inflation over online shops makes it beyond unreasonable sometimes.

ya calculating the power usage is very easy if you know watts and volts of what you are hooking up. watts/volts=amps then its directly comparable to alternator specs.

when you get a new alternator make sure you have a 20% power gap if you don't want it to die early due to stress.

This post was edited by Subwoofer on Jun 16 2013 05:03pm