Based on your profile you are in BC, so if it takes your truck 20 minutes to warm up in Northern BC honestly I think something is up with your heating system. I lived in Yellowknife for years, so way colder on average than you're ever gonna see anywhere in BC and it generally took 5-6 minutes at regular idle. If you see -50c actual in BC then it'll be damn near the coldest day in recorded history.

That being said if you are going to use a coolant heater in my experience you need a pump one. A lower rad hose unit does just that, heat only the coolant in the lower hose. Ya they're easy to install but they don't move the fluid much in real cold, convection only so your engine block is still pretty cold. Also until the thermostat opens all the warmed fluid is mostly sitting in your rad, versus putting a pump unit in up by the heater core and having actual hot fluid where you need it.
Additionally if you don't want to mess with freeze plugs for a block heater there's tons of alternatives: external bolt-on or magnetic, or the larger adhesive pad units that cover the bottom of your oil pan.

All of these options should be available at your local Lordco, Canadian Tire, Napa, Bumper to Bumper or whatever. Hell Walmart sells this stuff in Canada. Way more cold weather options here than down south.

*Edited for clarity

 

Good luck on getting the coolant to 170*. Typically they warm the coolant to 100* which intern warms the engine to about the same temp. It would be like starting your truck on a 90-100* day

 

The plug in is on a 15 amp breaker. I do not live in BC anymore. I only got this truck 2 months ago from southern BC so currently it has no block heater of any kind. 20 minutes may be an exaggeration but it takes too long to blow heat for my liking with any vehicle. I'm probably going to go with a circulating/pump heater from the bottom petcock to the heater return with a one way check valve preventing backflow. I'm honestly not too familiar with the cooling system but I want it hot at any rate.

 

All you need to do is cut a heater hose and put it in line.

No need to complicate things with check valves and such.

Also, have you ever tried to put cardboard in front of the radiator? That cuts warm up time in half.

OR, an electric fan setup(no airflow when idling unless called for)

 

Use a smaller unit or you will just cook the coolant.
Also a small glue on oil pan heater is a great idea.
If worried about the battery then use a battery blanket.

 

+1 on the cardboard, or you can even get cut to fit "winter fronts" that snap over the front grill. That plus a lower hose heater or circulating heater should have you sorted out.

 

I have the 1000 Watt zerostart heater rigged in. I also discovered a stock block heater hidden on the back of the engine while I was looking around, gonna double em up. I will post my findings of how well it works when it gets colder for others looking for this info.

 

I tested the coolant heater today. Shut the truck off two hours ago and plugged it in. Seems to be holding around 70 degrees farenheit. I imagine it will work better when I plug the factory heat in as well but for now it seems that the heater works pretty good. I was worried there would be air trapped in the hose as I had to go over the top of the engine from the drivers side to splice into the heater lines. It's -1 C out right now in case anyone is wondering.

 

How much is that in American?

 

30 Farenheit or 1 degree colder than water freezes at.

 

30.2 degrees

Anybody know where to get a cord for the stock block heater I assume that's what I have

 

Napa sells them